Cigarette filter and the incidence of lung adenocarcinoma among Tunisian population

Increasing incidence of lung adenocarcinoma (Ad) is observed for the last two decades in all over the world and may become the most frequent lung cancer subtype in the next years. Its increasing prevalence has been well documented in United States for the last two decades. Geographical differences in the increase of Ad prevalence was also reported in Europe where the Squamous Cell Carcinoma (SCC) still predominates but the increase of Ad incidence was shown in the beginning of 1980s. In Tunisia, the incidence of Ad was relatively low in 1990 when compared to western countries and was shown to continue to increase with a more important rise of Ad incidence over SCC type. In this study the time-dependent increased incidence of Ad is reported between USA, Europe and Tunisia. A lag-time period of 10 years is observed between Tunisia and Europe for this increased incidence in smokers and about 20 years between USA and Tunisia. According to the literature, changes in the types of cigarettes smoked as well as modifications in time and geographical trends seem to explain partly the increased incidence of Ad lung cancer.